Interlock



Dec. w, 1935. G B, THEM zmmsz INTERLOC K Original Filed June 21, 1933 T 7 INVENTOR.

Geo/7e B. 777/eme BY MWF/M ATTORNEY.

or nu Patented Dec. 10, 1935 UNITED STATES PATENT OFFICE INTERLOCK Application June 21, 1933, Serial No. 676,977 Renewed April 23, 1935 21 Claims.

This invention relates to interlocks and more particularly to interlocks which are adapted to lock electrical switches or other devices operable by a plurality of revolutions of a rotary shaft.

In certain switch installations it is necessary to complete a number of revolutions of a hand operated shaft to move the switch from one position to another and an object of the present invention is to prevent locking of the switch until the necessary number of revolutions have been completed. The interlock is of the key actuated type wherein the keys are adapted to operate similar interlocks and the keys are not removable until moved to a locking position.

Another object of the invention is to provide an interlock with a plurality of aligning openings and solid members which cooperate to lock the device except in certain predetermined positions.

Another object of the invention is to provide an interlock which is adaptable to a rotary actuated operating shaft.

A feature of the invention relates to an interfering plate which is adapted to block the movement of the main locking bolts except in certain predetermined positions of the shaft. In the illustrative embodiment the interfering plate is actuated by a nut which moves the plate into and out of interfering relation with the locking bolts, the nut being threaded on the shaft and having a cam slot cooperative with the interfering plate to move it radially of the shaft.

Other objects and features of the invention will be apparent from the following description in connection with which a preferred embodiment of the invention has been shown in the accompanying drawing in which,

Fig. 1 is a side elevation of the device with cover removed and partly in section;

Fig. 2 is an elevation of the shafts and parts thereon, taken at right angle to that in Fig. 1;

Fig. 3 is a section through the interfering plate, taken along line 3--3 of Fig. 1;

Fig. 4 is similar to Fig. 3, except that the interfering plate is in a locking position; and

Fig. 5 is a modification of the nut shown in Fig. 2 for use when a neutral locking position is required.

Fig. 6 is a sectional view illustrating one method of preventing the removal of the key except 'in the locked position; Fig. 7 is a plan view of the lock shown in Fig. 6.

Referring to the drawing, the interlock which may be applied to either ahorizontally or a verticallymounteddisconnecting switch (not shown) consists of a casing 3 secured as by means of bolts 4 to a column 6. Journalled vertically through casing 3 is a shaft 1, the lower end of which (as viewed in Fig. l) is coupled to a gear box 8 operable by hand crank 9 and the upper end of which is coupled to a switch operating pipe or sleeve l I. 5 Also connected to the shaft by a pin I2 is a lead screw l3 upon which moves a nut l4 (best shown in Fig. 2) each side of which is machined flat and equipped with a groove [6, comprising a straight central portion and an inclined portion at each 10 end thereof. Surrounding the nut is an inter fering plate ll having inwardly projecting tongues l8 registering with grooves l6 forming face cams for the guidance of the tongues. From the external side of the plate protrude ears I9, each of which contains a slot 2| through which are inserted screws 22 and about which, by means of sleeves 23, the plate is supported, the interfering plate being radially slidable between the screw head and sleeve The ears I 9 further contain square openings 24 so located that they admit the slidable interlock bolts 28 of the same shape, and are in alignment with the bolts only when tongues H? are in the inclined end portions of the groove [6. When nut I 4 is in an intermediate po- 25 sition the central portion of groove It moves plate I! to the position shown in Fig. 4, wherein the plate openings 24 are out of alignment with bolts 26 causing bolts to be immovable. These bolts are parallel to, and equidistant from the shaft 1 and 30 are slidably mounted in wall 21 of the housing 3 in which the shaft is journalled, the lower portion of each bolt being connected through a pin and slot arrangement with a rotatable arm 28 whose movement is controlled by rotation of a key 25 5 which is inserted in the cylinder lock 25a, to which the arm is attached.

The locking of bolts 26 is accomplished through means of a notched wheel 29, secured to shaft 1 by a pin 32 and abutting a boss on the under side of the wall 2'! as viewed in Fig. 1. By undercutting the periphery of the wheel, two cylindrical disks, 33 and 34 respectively, are formed around the outside edge of the wheel which revolves upon operation of the shaft through 5 grooves 36 milled across the inner side of the bolts 26. Likewise, the disks have grooves or notches 3'! milled across their periphery on opposite sides to permit the sliding of bolts 26 in certain positions of wheel 29.

It is preferred to use locks of the well known type in which the key is removable only in the locked position, therefore it is apparent that in the position of the parts 'as shown in full lines in Fig. 1,.the keys are not removable but the handle 55 be seen that the key 25 is not removable from.

lock 250. until the projection 3! on the key aligns with notch 30, and that this position of the key corresponds to the locked position of bolt ZBillustrated in broken lines in Fig. 1. It is understood that this interlock is intended. for use with.

other similar interlocks operated by the. same keys whenever they are released by a'move ment of the bolts 26 corresponding to the locked position of the locks 25a. Thei shaft '1: be locked in the position shown in Fig. 1 by move ment of either bolt 26 or may be locked in a po- -sition wherein nut I; has moved to the dotted line position of Fig, 2, but cannot'be locked in any intermediateposition because of the action of interfering plate [1. 'If it were not for the interfering plate the shaft 1 could be looked after degrees rotation if. notches 31 are identical or after 3 de e i he are ne ua shape or size, but. by the use of the interfering'plate locking is prevented until the nut I4 is in a position wherein the openings 2 4 are in alignment with the bolts and which may be any multiple of 180 or 360. degrees. l

If it is desiredto provide an interlock in which the switch may be lockedin an intermediate position, the nut MA shown in Fig. 5 may be used. In this, form of the invention the groove SA is provided with a V-sh'aped portion 38 wherein the tongues 18 will be guided to a position wherein a the openings 24 are aligned with bolts 26.

Inthe operation of the device if it is desired,

to actuateanother. interlock of similar construction, one of keys 25 willbe rotat'ed'to' move bolt 25 to the dotted line position. 7 Key 25 may then be removed for actuation of the second interlock, but the first interlock will prevent actuation of the switch because. notches"3.5f and 31 will not be in' alignment. If the second interlock is identical with thelone shown, both keys will have to. be removed for use in the second interlock, but it is understood that the second interlock may be operable by a single key inwhichcase the second e e lab e f a i reinterl qk- Th ey r e ealm b e. nt l belts. hav beenm red to locking position, therefore as the bolts can only be moved in certain;po sitions of the interfering plate. I1, the operator is assured that no other interlock can be operated without the. switch being in a. predetermined position.

While a preferred embodiment of the inven ated by shaft rotation for locking the bolt] 2. In an interlock, a rotatable shaft, an axially movable bolt adjacent the shaft f01 '10kil'l g the same, a movable memberactuatedby shaft rotation for locking the bolt, andsaid member having an opening therein movable into and out of registration with the end of said bolt.

' l 3. In an interlock, a rotatable shaft, an axially movable bolt adjacent the shaft for locking the same, and a transversely movable member actuated by shaft rotation, said member being adapted to move into locking relation with the bolt only after a plurality of shaft revolutions.

4. In an interlock, a rotatable shaft, an axially movable bolt adjacent the shaft for locking the same, a transversely movable member,'said member being adapted to move into locking relation with the bolt only after a plurality of shaft revolutions, a nut threaded on the shaft having means thereon coacting with the radially movable -member to actuate the same, and means preventing rotation of the nut.

' 5. n, an interlock, a rotatable shaft having a collar thereon provided with a peripheral notch,

abolt parallel to the shaft and slidable in the notch, said bolt having a notch adapted to align with the collar in one position of the bolt, means for sliding the bolt, and means actuated by shaft rotation for preventing sliding movement of the bolt;

.6. In an interlock, a rotatable shaft having a collar thereon provided with a peripheral notch, a bolt parallel'to the shaft and slidable in the notch, said bolt having a notch adapted to align with the collar in one position of the bolt, means for sliding the bolt, and means actuated by shaft rotation for preventing sliding movement of the bolt, said means including a transversely movable member adapted to interfere with the end of the bolt. 7

7. 'In an interlock, a rotatable shaft having a collar thereon provided with a peripheral notch, a movable bolt parallel to the shaft and slidable in the notch, said bolt having a notch adapted to align with the collar in one position of the bolt, meansfor sliding the bolt, and means actuated by shaft rotation to engage the bolt for preventing sliding movement of the bolt.

8. In an interlock, a rotatable shaft having a collar thereon provided with a peripheral notch,

a bolt parallel to the shaft and slidable in the notch, said bolt having a notch adapted to align withthe collar in oneposition of the bolt, means for sliding the bolt, and means actuated by shaft rotation for preventing sliding movement of the bolt only after a plurality of shaft revolutions.

9. In v an interlock, a rotatable shaft. having a collar provided with a notch, a bolt having a notch'slidably mounted in the collar notch for locking the shaft against rotation, said shaft having a threaded member thereon, an axially movable nut on said threaded member having a cam groove, a transversely movable member adapted to interfere with bolt movement and having means thereon cooperative with the groove to move the member, and means. for preventing rotation of the member and the nut.

10. In an interlock, a, rotatable shaft having a collar provided with a notch, a bolt having. a notch slidably mountedin the collar notch for locking the shaft against rotation, said shaft having a threaded member thereon, an axially movable nut on said threaded member having. a cam groove, a transversely movable member adapted to interfere with bolt movement and having means thereon cooperative withv the groove to move the member, and means, for preventing rotation of the member and the nut, said member being arranged to interfere with bolt movement only in theextreine positions of the nut,

11. In an interlock, a rotatable shaft having a collar provided with a notch, a bolt having a notch slidably mounted in the collar notch for locking the shaft against rotation, said shaft having a threaded member thereon, an axially movable nut on said threaded member having a cam groove, a transversely movable member adapted to interfere with bolt movement and having means thereon cooperative with the groove to move the member, means for preventing rotation of the member and the nut, and manually operable means for actuating said bolt.

12. In an interlock, a rotatable shaft, a slidable bolt for locking the shaft against rotation, a member slidable at right angles to the bolt, said member having an opening large enough to receive the bolt, and means actuated by shaft rotation for moving said opening into and out of alignment with said bolt.

13. In an interlock, a rotatable shaft, a slidable bolt for locking the shaft against rotation, a member slidable transversely of the bolt, said member having an opening large enough to receive the bolt, and a cam actuated by shaft rotation cooperating with the member to move the opening into and out of alignment with said bolt.

14. In an interlock, a rotatable shaft, an axially movable bolt adjacent the shaft for locking the same, means for moving the bolt, and a member transversely movable by shaft rotation into and out of loclnng relation with the ends of said bolt.

15. In an interlock, a rotatable shaft, a pair of axially movable bolts adjacent the shaft each of which is axially movable to lock the shaft, and a transversely movable member actuated by shaft rotation for simultaneously locking both of said bolts.

16. In an interlock, a rotatable shaft having a collar thereon provided with a pair of spaced peripheral .notches, a pair of bolts parallel to the shaft and slidable in the notches respectively, each of said bolts having a notch therein adapted to align with the collar in one position of the bolt for permitting rotation of the collar therein, means for selectively moving each bolt, and means actuated by shaft rotation for simultaneously preventing sliding movement of both bolts only after a plurality of shaft revolutions.

1'7. In an interlock, a rotatable shaft, a movable bolt adjacent the shaft for locking the same, a member movable along said shaft by rotation thereof, and a second member movable into and out of locking relationship with said bolt, said second member being actuated by the first mentioned member.

18. In an interlock, a rotatable shaft having a threaded portion, a nut on said threaded portion, means preventing rotation of the nut, means preventing axial movement of the rotatable shaft, a bolt for locking said shaft, and means movable by said nut into and out of locking relationship with said bolt.

19. In an interlock, a rotatable shaft having a threaded portion, a nut on said threaded portion, means preventing rotation of the nut, means preventing axial movement of the rotatable shaft, a bolt for locking said shaft, and means movable by said nut into and out of locking relationship with said bolt, said means having two non-locking positions and a locking position intermediate said non-locking positions.

20. In an interlock, a rotatable shaft having a threaded portion, means preventing axial movement of the shaft, a nut on said threaded portion,

means preventing rotation of said nut, a bolt for locking said shaft against rotation, and a locking member for said bolt, said member being movable by said nut and having spaced bolt receiving openings therein adapted to align with said bolt at corresponding positions of the nut and an intermediate portion preventing movement of said bolt to a locking position with said shaft.

21. In an interlock, a rotatable shaft having a threaded portion, means preventing axial movement of said shaft, a nut on said threaded portion, means preventing rotation of said nut, a collar having an opening secured to said shaft, a bolt movable into and out of engagement with the opening to lock the shaft, and a member movable by said nut into and out of locking engagement with said bolt, said member having two non-locking positions and an intermediate locking position.

GEORGE B. 'I'I-IIEME. 

